Resilient cap for the keys of typewriters or similar machines



June s, 1925. 1,541,645

R. s. GRAHAM REsILIEnIcAP FOR THE KEYS oF TYPEWRIIERS oa SIMILAR MACHINES Filed May Iv, 1924 I N V EN TOR. #oaf/fr s. @ff/HHM *IQ-III A TTORNE Y.

` clfeetlo the lingers of the operator.

Patented June 9, 1925.

UNITED STATES PATENT OFFICE.

nonnen s. GRAHAM, on new Yorin, n. Y.,nss1e1\ion on emanate 'ro'zWILLrs M.

Fontaine, er new 'Yeni/r, ne.

`RESIIJIENT CAP FOR THE 'lYS O2? TYPEWRITERS @dit SIMLAR MAGHINES.

.Application lvediiay 1?,V 1924. v'Serial No. 713,341.

scription, such as will enableothers skilled .in the art to which it appertains to make and use thensame.

This invention Vrelates to a resilient cap for the keys `oftypewritersa or .similar machines, andthe objects ot'the invention are toiprovide a resilient or cushioned cap that is interchangeable without reference tothe index `letter or numeral of the key toV which it is to be applied. Further objects of the invention are `to :provide a cap :that WillA` when applied to akey7 have a dish `shaped topprovided Vwith cushion -members y surrounding an? opening, said cushion members being provided with cushion supports ad-l jacent ,said open-ing .which `will act to permit of the cushion members being'progressively flexed to provide aresilient cushioning `Beterriug tothe drawings:

Figure 1 is a perspective `view ofthe key end et a keybar of a typewriter, or similar machine7 provided with aresilient cap made `1n accordance with the/invention.

Figure 2 is an enlarged top View of Fig. 1.

Figure 3 is a-seetional view onthe line 33ot` Fig. 2. i VFigure 11 is a seetionalview on the line Figure 5 is a bottom viewofzthe cap.

In the drawings 1ldesignatestheLkeyend ot an ordinary` typewriter barter key end otany similar machine. which is provided iu the :present instance with the usualfkey compris' k a circular disk 2 haringen its upper sur-tace an index letter ornumerah the' saine being covered with a .circular disk S oi glass, both supported on a `metal-key base 1 having an upturned edge 5 and a shank t3 secured to the upturned portion ot the key bar. The disks 2 and 3 are-held in position ou the top of the key base 11 by means et a` cireularlange 7 surrounding the outer edge of the upturned edge 5 and crimped overthe top thereof, and the cir cumferential edges ot the disks 2 and 3 so as to provide a circular beaded edge 8.

`The beadededge S-ofthe circular -flange` 7 forms a continuous beador ridge about-the `upper-surface of the key not onlylto secure the. parts of the key together` but also toprovide a. suitable working surface lfor i the ingersef gthe voperator Ato Aprevent slipping,

the circumferential beadlor ridge 8A extendingiujnward above the surface of thekey to accomplish ,this purpose.

`The typewriter' key. above ,described i is similar te the typewriter `keysfin use on a Vgreat variety of typewriters and similar key operated niachinesfand is adapted tofbe covered by a removable resilentjrubb'er cap 9 made in accordance Withjthe presentinvention.

v The typewriter key cap -9 is, in accordance `with the presentk invention, ,preferably made oji rubber suitably; molded! to-v proyideahollow disk', shaped cap comprising acylindrical body 10k, lthe `inner diameterV of `which is less than Vthe* outer di ameter'- e1 the key,` 1.the key cap being.- open atfthebottom and kprovided with aninnerguide flange l-lythefinner .edgeof `-whichiscut-to flare outwardas shown at l1,2 to `facilitate the tkeylcapnbeing forced over the toplof the. key after lwhich theguide flange lliassumes noiinallocked position against -the bottom 'ofthe key ,-as shown in Fig. 3 and Fig. 4. o f

The keycap` 9 is also, in aecordance'with the present invention, provided ywith a flat topper slightly dished top, having side and end cushion `members 13 and 14, .which surroundma top opening so ast-o `make visib'lethe indexletter orl numeral on the disk 2.1 ,In-the present instance the top opening inthe key -cap 9 is madeqgreatei.' kinilength.than in breadth, the greater length being in the direction of the -keybar to more easily -show the index letter or numeral, althoughtif desired thetop opening` can belm'ade ron-nd er other ,convenient shape toffexpose the yindex `letter or numeral; hoivever,the =eloligatedV opening vas shown innthe drawingsisstoqbe preferred. c l

The side and end` .cushion` members 13 .and

\ 1f1` are preferably. m ade` ofv uniformrrthickness and preferably thicker than the sidesl ofithe cylindrical body portion V10. `In'the present slightly lover thebeaded 'edge 8 offthedrey .and rest upon the same, as shown in Fig.` 3,

Ainstance the .end cushion members .ltextend edge 8 of the key, the outer edge restingupon the same while the inner edge of the cushion members are provided with integral supports which rest upon the upper surface of the glass disk 8, as shown in Fig. 8 and Fig. 4l. v. l

In the present instance the supports 15 are preferably made quarter-spherical in shape in order to provide progressively increasing resistance as the same are forced `downward by the finger of the operator.

well as being tapered in both directions along t-he side of the opening, shown in the drawings.

In order to make the top of the key cap more resilient and also to provide a greater view of the index letter or numeral on the keythe inner edges of the side cushionmembers 13 and the supports 15 are suitably beveled or undercut as shown yat 1G. The undercutting ofthe inner edgesy of the side cushion members permits of the opening'in the topfof the cap being made relatively *smallv without obstructing to any great extent a clear view ofthe index letter or numeral on the key; the same also acts -to obviate glare or reiieetion of light froril the surface of the key, besides giving a certain resiliency to the top of the cap when. struck bythe finger of the operator, due to the overhanging portions of the side cushionl members, the supports 15 acting to progressively cushion the blow as the key is 'forced downward, to give a relatively firm resilient touch.

A key cap made as above describedwvi'll, when forced over the top of akey, act, Iby

4reason of the raised beaded edge S on the circumference 'of `the key, to become dish shaped with the lowermost edge of the sup-- ports 15 resting upon the upper surface of the glass disk 3. rlhe dish shape of the top of the key cap is caused not only by the fact that the same may have a preliminary dish shape when molded, but also to the fact that the inner circumference of the body portion 10 being less than the outer circumference of the key acts to dish the cap at the centre which it is permitted to do as the ends of the supports 15 are arranged to be of sufficient depth to permit of the central portion of the cap being dished before the supports rest upon the topV of the glass disk 3 of the key.

as clearly F rom the above description it will bf seen that a resilient cap is provided which can easily be forcedvover, or removed from, the top of a key for a typewriter, or similar machine, and that the same will in View of its construction provide a dish shaped top, or working surface, that will permit of the same being progressively iiexed by the iinger ofthe operator to progressively cushion the kblow when struck.

lli/*bile the invention has been described with particular reference to the details et construction, the same is not to be considered as limited thereto as manychanges can be made and still fall within the scope of tlu` invention set forth inthe following claims.

What I claim is: y.

1. A resilient cap for typewriter and similar keys provided with an upwardly extending circumferential ridge, said eap being made in the form of a hollow disk having a top opening, side cushion members adjacent said top opening, and supports secured to said vside cushion members, said cushion members'and supports being tapered from the edge of said top opening in ward toward the ridge of said key as well as being taperedin opposite directions along the side .of said opening, said supports being arranged to engage the top of said-key when the capfis forced over the top of said key.

2.A;res1lient cap for typewriter and similar keys comprising a top and integral` circular tlangerof elastic material, theV said top being formed with a slot; elastic supporting members dependingfrom the under side of saidtop adjacent the slot therein,y the said supporting members being of quartei=spherical shape andadapted for Contact with tlieface of a key over a small area at either side of said slot.

A resilient cap for typewriter and similar keys provided with an upwardly extending circumferential ridge, the said cap comprising a circular flange of elastic material. and a Vtopintegral therewith, the said'top being composed of front and rear flanges and `side cushion members defining a slet in the center of said cap, the front and rear flanges being adapted to rest on the circumferential ridge of the key; depending supports integral with said side cushion members and adjacent the slot, thc

rsaid supports being of quarter-spherical.

shape and adapted for contact with 'the fare of a key over a small areaY at either side oi said slot.

In testimony whereof have signed this yspecification in` the presence ofV two subscribing witnesses. Y

Y ROBERT S. GRAHAM,

lVitnesses y 'Lne J. Mn'r'rr,

' LILIAN E. PORTER. 

